Question

I’m creating a custom layout class and the views within the layout are sizing properly.
The problem I’m having is that if I include another layout within that one the size of all the nested view’s children are basically full screen sizes.

XML Layout Code – The contents within the FrameLayout are not sizing properly.

<CustomLayout>
<ImageView android:layout_height="wrap_content" android:layout_width="wrap_content"/>

<FrameLayout android:layout_height="wrap_content" android:layout_width="wrap_content">
  <!-- The views in here are sizing themselves as full screen. -->
  <include layout="@layout/panel_emptypicture" android:id="@+id/EmptyPictureRelativeLayout" android:visibility="visible" />
</FrameLayout>
<EditText android:layout_height="wrap_content" android:layout_width="wrap_content" />
<EditText android:layout_height="wrap_content" android:layout_width="wrap_content" />
</CustomLayout>

Java Code for custom layout.

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    final int numChildren = getChildCount();

    Dimension d = new Dimension(0, 0, this.getWidth(), this.getHeight());
    final float scaleX = this.getWidth() / virtualWidth;
    final float scaleY = this.getHeight() / virtualHeight;

    for(int i = 0; i < numChildren; i++) {
        final View child = getChildAt(i);
        final LayoutParams lp = (LayoutParams) child.getLayoutParams();
        final Dimension lpd = lp.getDimension();

        Dimension dest = lpd.scale(scaleX, scaleY, d);
        child.layout(dest.x, dest.y, dest.width + dest.x, dest.height + dest.y);
    }
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);

    int width, height;
    float maxWidth = MeasureSpec.getSize(widthMeasureSpec);
    float maxHeight = MeasureSpec.getSize(heightMeasureSpec);

    final float widthVirtualMultiplier = virtualWidth / virtualHeight;
    final float heightVirtualMultiplier = virtualHeight / virtualWidth;

        if(maxWidth * heightVirtualMultiplier < maxHeight) {
            width = (int)maxWidth;
            height = (int) (width * heightVirtualMultiplier);
        } else {
            height = (int)maxHeight;
            width = (int)(height * widthVirtualMultiplier);
        }


    setMeasuredDimension(width, height);

    // Tried adding this to see if it would do anything. Nope, no effect.
    final int numChildren = getChildCount();
    for(int i = 0; i < numChildren; i++) {
        final View child = getChildAt(i);
        measureChild(child, widthMeasureSpec, heightMeasureSpec);
    }

}

Answer 1

This ended up being the code that was stable enough for my needs. It still had the bug but oh well.

The entire project is hosted here if you need the other referenced classes. http://code.google.com/p/motivatormaker-android/

package com.futonredemption.makemotivator.widget;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Rect;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewDebug;
import android.view.ViewGroup;

import com.futonredemption.makemotivator.util.RectUtils;

public class ScaledCompositeLayout extends ViewGroup {

    @ViewDebug.ExportedProperty(category = "virtual-measurement")
    public float virtualHeight;

    @ViewDebug.ExportedProperty(category = "virtual-measurement")
    public float virtualWidth;

    @ViewDebug.ExportedProperty(category = "clamp-width")
    protected boolean clampOnWidth;


    public ScaledCompositeLayout(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public ScaledCompositeLayout(Context context, AttributeSet attrs,
            int defStyle) {
        super(context, attrs, defStyle);

        final TypedArray styleValues = context.obtainStyledAttributes(
                        attrs,
                        com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout,
                        defStyle, 0);

        virtualWidth = styleValues.getDimension(
                        com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_VirtualWidth,
                        -1);
        virtualHeight = styleValues.getDimension(
                        com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_VirtualHeight,
                        -1);
        clampOnWidth = styleValues.getBoolean(
                com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_ClampOnWidth,
                false);

        styleValues.recycle();

        if(virtualWidth == -1) {
            throw new IllegalStateException("virtualWidth is required parameter.");
        }
        if(virtualHeight == -1) {
            throw new IllegalStateException("virtualHeight is required parameter.");
        }
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        final int numChildren = getChildCount();

        Rect parentRect = new Rect(0, 0, this.getWidth(), this.getHeight());
        final float scaleX = this.getWidth() / virtualWidth;
        final float scaleY = this.getHeight() / virtualHeight;

        for(int i = 0; i < numChildren; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            final RectF lpr = lp.getRectF();

            Rect dest = RectUtils.scale(lpr, scaleX, scaleY, new RectF(parentRect));
            child.layout(dest.left, dest.top, dest.right, dest.bottom);

            //Dimension out = dest;
            //throw new IllegalStateException(String.format("Position: %d x %d -- Size: %d x %d", out.x, out.y, out.width, out.height));
        }
    }

    /**
     * Uses the Virtual Width and Height to determine the ratio size of the actual layout.
     * The layout_width and layout_height parameters are used to determine the maximum bounds.
     */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        int width, height;
        //int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        //int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        float maxWidth = MeasureSpec.getSize(widthMeasureSpec);
        float maxHeight = MeasureSpec.getSize(heightMeasureSpec);

        if (maxHeight == 0.0F) {
            clampOnWidth = true;
        }

        final float widthVirtualMultiplier = virtualWidth / virtualHeight;
        final float heightVirtualMultiplier = virtualHeight / virtualWidth;

        //final float widthActualMultiplier = maxWidth / maxHeight;
        //final float heightActualMultiplier = maxHeight / maxWidth;
        /*
        if(widthMode == MeasureSpec.EXACTLY) {
            width = (int)maxWidth;
            height = (int) (maxWidth * heightVirtualMultiplier);
        } else if(heightMode == MeasureSpec.EXACTLY) {
            width = (int)(maxHeight * widthVirtualMultiplier);
            height = (int)maxHeight;
        } else { // Use scaling */
            if(clampOnWidth || maxWidth * heightVirtualMultiplier < maxHeight) {
                width = (int)maxWidth;
                height = (int) (width * heightVirtualMultiplier);
            } else {
                height = (int)maxHeight;
                width = (int)(height * widthVirtualMultiplier);
            }
        //}

        setMeasuredDimension(width, height);

        final int numChildren = getChildCount();
        final float scaleX = width / virtualWidth;
        final float scaleY = height / virtualHeight;
        final Rect parentRect = new Rect(0, 0, this.getWidth(), this.getHeight());

        for(int i = 0; i < numChildren; i++) {
            final View child = getChildAt(i);
            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
            final RectF lpr = lp.getRectF();

            Rect dest = RectUtils.scale(lpr, scaleX, scaleY, new RectF(parentRect));

            this.measureChild(child, MeasureSpec.makeMeasureSpec(dest.width(), MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(dest.height(), MeasureSpec.EXACTLY));

            //Dimension out = dest;
            //throw new IllegalStateException(String.format("Position: %d x %d -- Size: %d x %d", out.x, out.y, out.width, out.height));
        }

        /*
        for(int i = 0; i < numChildren; i++) {
            final View child = getChildAt(i);
            measureChild(child, widthMeasureSpec, heightMeasureSpec);
        }
        */

        //throw new IllegalStateException(String.format("%d x %d -- Physical: %.0f x %.0f -- Virtual: %.0f x %.0f", width, height, maxWidth, maxHeight, virtualWidth, virtualHeight));
    }

    @Override
    public LayoutParams generateLayoutParams(AttributeSet attrs) {
        return new ScaledCompositeLayout.LayoutParams(getContext(), attrs);
    }

    @Override
    protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
        return p instanceof LayoutParams;
    }

    @Override
    protected ViewGroup.LayoutParams generateLayoutParams(
            ViewGroup.LayoutParams p) {
        return new LayoutParams(p);
    }

    public static class LayoutParams extends
            android.view.ViewGroup.LayoutParams {

        public RectF virtualRect = new RectF();

        public RectF getRectF() {
            return virtualRect;
        }

        public LayoutParams(Context c, AttributeSet attrs) {
            super(c, attrs);
            float virtualWidth;
            float virtualHeight;

            TypedArray styleValues = c
                    .obtainStyledAttributes(
                            attrs,
                            com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_Layout);
            virtualRect.top = styleValues
                    .getDimension(
                            com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_Layout_VirtualTop,
                            0);
            virtualRect.left = styleValues
                    .getDimension(
                            com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_Layout_VirtualLeft,
                            0);
            virtualRect.right = styleValues
                    .getDimension(
                            com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_Layout_VirtualRight,
                            0);
            virtualRect.bottom = styleValues
                    .getDimension(
                            com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_Layout_VirtualBottom,
                            0);

            virtualWidth = styleValues
                    .getDimension(
                            com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_Layout_VirtualWidth,
                            -1);
            if (virtualWidth > 0) {
                virtualRect.right = virtualRect.left + virtualWidth;
            }

            virtualHeight = styleValues
                    .getDimension(
                            com.futonredemption.makemotivator.R.styleable.ScaledCompositeLayout_Layout_VirtualHeight,
                            -1);
            if (virtualHeight > 0) {
                virtualRect.bottom = virtualRect.top + virtualHeight;
            }

            styleValues.recycle();
        }

        public LayoutParams(int width, int height) {
            super(width, height);
        }

        public LayoutParams(ViewGroup.LayoutParams source) {
            super(source);
        }
    }
}